Roll heater



April 11, 1939.

E. B. DUNKAK' 2,153,958

ROLL HEATER Filed March 25, 1937 5 Sheets-Sheet l ROLL HEATER Filed March 23, 1937 3 Sheets-Sheet 2 LJi E. YB. DUNKAK April 11, 1939.

ROLL HEATER 5 Sheets-Sheet 5 Filed March 23. 1957 Ill'l lil r1 GKMMM Patented Apr. 11, 1939 UNITED ()FFIC ROLL HEATER Application March 23, 1937, Serial No. 132,504

12 Claims.

This invention relates to a heater for the heating of rolls used in the rolling of sheets from heated bars by passing them between a pair of relatively large rolls. These rolls are generally solid and require pre-heating in some manner before they give the best results on the long bars usually passed between them. Early practice was to gradually heat the rolls by passing short bars between them which were rolled out into comparatively short sheets of plate. Later practice has been to heat the rolls by electrical means.

This invention contemplates heating the rolls by radiation from fluid fuel heated elements. According to this invention a plurality of these fluid fuel heated elements are placed around the rolls and preferably inside a cover and the rolls may be gradually heated by varying the supply of the combustion fluid to the elements. Heating by radiation allows a much more even distribution of the heat around the surface of the roll so that the heat is much more evenly transferred to the total surface of the roll. It has been found in practice that the rolls may be brought to rolling temperature at considerably less expense than has been involved in the prior practices.

The heating elements are preferably heated by a fluid fuel which has mixed with it sufiicient oxygen or air to allow for a complete combustion of the fluid fuel in order both to give the greater economy in the use of the fuel and to prevent any injurious particles from passing into the atmosphere. Exposed flames are of course eliminated by carrying on the combustion in an enclosed element. This also prevents the flames from contacting the roll and causing the same to scale or be otherwise adversely affected by the heat. The fuel used is preferably a mixture of air and gas or oil combined in accurate proportions to effect complete combustion. With this heater it has been found that the rolls may be brought to a proper temperature more rapidly than with any other heating means now available.

The heater may be made for a standard length of roll and there is shown an extension which may be placed at one or both ends of the roll when a longer roll is to be heated than that for which the heater is originally intended, these extensions retaining the heat given out by the heater and thereby extending its effectiveness for the length of the roll.

The invention will be more clearly understood from the following description and the accompanying drawings forming a part hereof which show a few only of the forms which the invention may take.

In the drawings:

Figure 1 is a perspective view of the heater with an extension applied to each end.

Figure 2 is a sectional view of the heater and extension substantially on line 2-2 of Fig. 1, showing their relation to a roll.

Figure 3 is a sectional view of the heater and its adjusting means substantially on line 33 of Fig. 1.

Figure 4 is a fragmentary sectional View of the arrangement of the heating elements shown in Figs. 1 to 3 inclusive.

Figure 5 is a fragmentary sectional view of a modified form of heating element.

Figure 6 is a fragmentary view of a further modified form of heating element.

Figure '7 is a fragmentary view of a further modified form of heating element.

Figure 8 is a fragmentary view of a further modified form of heating element.

Figure 9 is a fragmentary view of a further modified form of heating element.

In the drawings similar numerals refer to similar parts throughout the several views.

The heater shown in Fig. 1 is intended to be placed about a pair of rolls between which the bars are passed for rolling them into relatively Wide sheets. The heater is made in two sections each of which comprises a frame structure of T' bars I to which are welded near their ends as shown two semicylindrical casings 2 which are composed of metal sheets on the outside 3 and on the inside 5 and with heat insulating material 5 between. To each end of the inside of the casings 2 are welded channel bars 6. Passing through holes in these channel bars are a plurality of tubes 7. The tubes are preferably rolled into the channel at one end and slide in the channel at the other end to allow for expansion and contraction due to temperature changes. These tubes 1 are preferably placed parallel to one another and also parallel to the axis of the casings 2. The channels 6 are preferably cut as shown at 8 to allow for their flexing around the roll. Manifolds 9 are placed one at each end of each casing section and these manifolds are in the form of tubes attached by brackets 10 to the casing. The manifolds have burners I l arranged to pass into the tubes '5 a combustion mixture of fluid fuel. The burners from each manifold are directed'into alternate tubes, from one end of the casing into each alternate tube and from the other end of the casing into the other alternate tube; preferably the burners enter the tubes at the end that the tubes are rolled into the channels 6. The orifice at the opposite end of the tubes is somewhat constricted as shown at l 2 to allow for the exhaust of the consumed products of combustion. The combustible mixture is supplied to the manifolds by pipes l3, branching from pipes M. The arrange ment of the burners in alternate ends of the tubes makes sure an even heating effect for both ends of the rolls. Valves l5 regulate the supply to each manifold. The combustible mixture is supplied to the main pipe M from a carburetor or other supply not shown.

The casings 2 are preferably welded to the T bars I only adjacent the ends of the T bars and the casing may be bent around the rolls to be in closer proximity to them by means of the adjusting screws I6 passing through threaded members I! secured to the channels I8 welded to the T bars 5. The screws IS bear upon angle clips l9 welded to the unattached sides of the casings 2. The assembled two sections of the heater are placed upon the rolls by any kind of lifting means hooked upon handles 20. passing through plates 2l--22 welded to T bars After placing the two sections of the heater around the rolls they are fastened together by means of throw bolts 23 which are pivoted in supports 24 welded to the casings 2 at one end and at the other end, the bolts pass through projecting U members 25 fast to the opposing section of the heater and the throw bolts have at their extremities nuts 28 which are drawn up against the U members 25 to hold the two sections of the casing together.

The extensions which may be placed at one or both ends of the heating members are made up of channels 2'5 to which casings 28 are welded at the extremities of the channels and these casings have therein insulating material 29 and throw bolt constructions 3G and casing size adjusting means 3| generally similar to that shown for the heater proper. The casings 2B are made thinner adjacent the heater as shown at .32 to allow for the casing to come Within the manifolds B so that the casing 29 may be placed adjacent to the channel 6 to retain the heat upon the rolls, as shown in Fig. 2, the roll being shown at 33.

The arrangement of the heating elements above described is shown in Fig. 4. A modified form of heating element is shown in Fig. 5 in which the burners enter adjacent legs of a continuously circulating element 34. The heated particles of combustion pass continuously around through the sides and the ends of the element. The exhaust for the burned products of combustion for this type of element is in the form of an enlarged opening into the element at the point of entrance for the burner.

A fLuther form of element 35, shown in Fig. 5, shows a continuously circulating tube for the products of a combustion with a single entrance for the burner and fluid fuel, very much as is shown in Patent No. 1,244,863 dated October 30, 1917, granted to W. W. Kemp et al. The exhaust for this type of heater is similar to the type of heater shown in Fig. 5.

A further modification is shown in Fig. 7 in which the elements 36 have the same form as those in Fig. 6 but in which the elements extend only approximately one-half the length of the heater casing.

In Fig. 8 a U shaped element 31' is shown in which the products of combustion pass through the U and out at the same side of the casing as that on which the burner is placed.

In Fig. 9 U shaped elements 38 are shown only passing about one-half the length of the casing.

It is of course apparent that these heating elements may be made in practically any form desired and many other modifications of the invention may be made without departing from the spirit of the invention.

It will be understood that a combustible mixture is passed into the heating tubes or elements at the desired rate and ignited and that the rolls may be readily brought to the heat required for rolling without danger of cracking or injuring the rolls.

What is claimed as new and is desired to be secured by Letters Patent of the United States is:

1. A roll heater, comprising a supporting frame to substantially surround a roll, a plurality of longitudinally closed tubular heating elements mounted in said frame to extend longitudinally of the roll, each said element having a passage therethrough and being provided with an inlet and a vent, a burner at each inlet to project ignitable fluid fuel into said heating element the fuel being combusted within the passage of said element and means facing the roll and said elements to direct the heat from the elements upon the roll.

2. A roll heater comprising a plurality of longitudinally closed tubular heating elements mounted in close parallel relation to each other to substantially surround a roll, means to support said elements in proximity to the roll, each said element being provided with an inlet and a vent, a burner at each inlet to project ignitable fluid fuel into said heating element the fuel being combusted within the tubular part thereof and means facing the roll and said elements to direct the heat from the elements upon the roll.

3. A roll heater comprising a plurality of longitudinally closed tubular heating elements arranged in close parallel relation to each other to substantially cover the surface of the roll, means to support said elements in proximity to the roll, each said element being provided with an inlet and a vent, a burner at each inlet to project ignitabl-e fluid fuel into said heating element the fuel being combusted within the tubular part thereof.

4. A roll heater comprising a plurality of longitudinally closed tubular heating elements each having a passage therethrough extending substantially longitudinally of the roll to be heated, means to support said elements in proximity to the roll, each said element being provided with an inlet and a vent, a burner at each inlet to project ignitable fluid fuel into said elements the fuel being combusted within the passage of said elements, and a manifold fuel supply for a plurality of said burners.

5. A roll heater comprising a plurality of heating elements each having a passage therethrough extending substantially longitudinally of the roll to be heated, means to support said elements in proximity to the roll, each said element being provided with an inlet and a vent, a burner at each inlet to project ignitable fluid fuel into said elements the fuel being combusted within the passage of said elements, various of said elements having the burner at one end, and others, at the other end.

6. A roll heater comprising a plurality of longitudinally closed tubular heating elements each having a passage therethrough extending substantially longitudinally of the roll to be heated, means to support said elements in proximity to the roll, each said element being provided 'with an inlet and a vent, a burner at each inlet to project ignitable fluid fuel into said elements the fuel being combusted within the tubular part thereof, and a manifold fuel supply at each end of the roll to supply fuel to a plurality of the burners at that end.

7 A roll heater comprising a plurality of heating elements having a passage therethrough extending substantially longitudinally of the roll to be heated, means to support said elements in proximity to the roll, each said element being provided with an inlet and a vent, a burner at each inlet to project ignitable fluid fuel into said elements the fuel being combusted within the passage of said elements, the burner inlets of said elements being arranged at one end of said elements in alternate elements, and at the other end in the other elements.

8. A roll heater comprising a plurality of heating elements each having a passage therethrough extending substantially longitudinally of the roll to be heated, means to support said elements in proximity to the roll, each said element being provided with an inlet and a vent, a burner at each inlet to project ignitable fluid fuel into said elements the fuel being combusted within the passage of said elements, the burner inlets of said elements being arranged at one end of said elements in alternate elements, and at the other end in the other elements, a manifold fuel supply at each end of said elements, to each of which burners are attached for the alternate inlets.

9. A roll heater comprising a plurality of longitudinally closed tubular heating elements each having a passage therethrough extending substantially longitudinally of the roll to be heated, means for adjustably supporting said elements to control their proximity to the roll, each said element being provided with an inlet and a vent, a burner at each inlet to project ignitable fluid fuel into said elements the fuel being combusted within the passage of said elements.

10. A roll heater for a pair of rolls comprising a pair of complemental heating sections for mounting in proximity to the set of rolls to be heated, said sections having therein a plurality of longitudinally closed tubular heating elements mounted in close parallel relation to each other, each element having a passage therethrough and an inlet, a burner at each inlet to project ignitable fluid fuel into said elements the fuel being combusted within the passage of said elements.

11. A roll heater for a pair of rolls comprising a pair of complemental heating sections for mounting in proximity to the set of rolls to be heated, said sections having therein a plurality of longitudinally closed tubular heating elements mounted in close parallel relation to each other, each element having a passage therethrough and an inlet, a burner at each inlet to project ignitable fluid fuel into said elements the fuel being combusted within the passage of said elements and a heat confining cover for confining the heat to said rolls.

12. A roll heater for a pair of rolls comprising a pair of complemental heating sections for mounting in proximity to the set of rolls to be heated, said sections having therein a plurality of longitudinally closed tubular heating elements mounted in close parallel relation to each other, each element having a passage therethrough and an inlet, a burner at each inlet to project ignitable fluid fuel into said elements the fuel being combusted within the passage of said elements and means to adjustably control the proximity of certain of said elements to the rolls.

ELMER B. DUNKAK. 

